Reappraisal of attributable mortality in critically ill patients with nosocomial bacteraemia involving Pseudomonas aeruginosa

In a retrospective study, population characteristics and outcome were investigated in intensive care unit (ICU) patients with hospital-acquired Pseudomonas aeruginosa bacteraemia admitted over a seven-year period (January 1992 through December 1998). A matched cohort study was performed in which all ICU patients with P. aeruginosa bacteraemia were defined as cases (N=53). Matching (1:2 ratio) of the controls (N=106) was based on the APACHE II classification: an equal APACHE II score (+/-1 point) and an equal diagnostic category. Patients with P. aeruginosa bacteraemia had a higher incidence of acute respiratory failure, haemodynamic instability, a longer ICU stay and length of ventilator dependence (P<0.05). In-hospital mortalities for cases and controls were 62.3 vs. 47.2% respectively (P=0.073). Thus, the attributable mortality was 15.1% (95% confidence intervals: -1.0-31.2). In a multivariate survival analysis the APACHE II score was the only variable independently associated with mortality. In conclusion, P. aeruginosa bacteraemia is associated with a clinically relevant attributable mortality (15%). However, we could not find statistical evidence of P. aeruginosa being an independent predictor of mortality.     

危重患者多药耐药鲍氏不动杆菌医院感染暴发的临床研究

目的探讨某院住院危重患者发生感染暴发流行多药耐药鲍氏不动杆菌(MDR-AB)感染聚集的原因与干预方式,旨在为预防和控制院内MDR-AB感染提供一定的理论依据。方法调查2017年6月1-7日7例住院危重患者MDR-AB感染聚集病例鲍氏不动杆菌分离与感染情况,采集患者呼吸道标本进行病原学鉴定和药敏试验,对患者病床环境及医护人员的手等部位进行环境卫生学监测。结果 7例MDR-AB感染病例均患有严重的基础疾病,使用呼吸机时间12～30d,感染时间集中在2017年6月1-7日;药敏试验结果显示,患者呼吸道痰液标本分离出的7株MDR-AB对哌拉西林、头孢他啶、美罗培南等14种药物均耐药,耐药率100.00%;对阿米卡星、磺胺甲噁唑/甲氧苄啶、四环素部分耐药,耐药率分别为71.43%、57.14%、42.86%;对左氧氟沙星、米诺环素、多黏菌素E均敏感或中度敏感;环境采样培养共分离出25株MDR-AB,与患者呼吸道痰液标本中分离出的7株MDR-AB具有较高的同源性,其中5株来自1、2、5、6、7号病例医护人员的手,5株来自2、3、4、5、7号病例的呼吸机管道,4株来自1、2、3、6号病例的床栏,4株来自2、4、5、6号病例的被褥,3株来自3、4、5号病例的治疗车,2株来自4、7号病例的床头柜,2株来自1、5号病例的呼吸机进出口。结论医院环境因素与医护人员因素是本次MDR-AB感染暴发的主要原因,通过严格的环境消毒与手卫生可以有效避免MDR-AB感染。     

Acquisition of multidrug-resistant organisms among hospital patients hospitalized in beds adjacent to critically ill patients.

OBJECTIVE: To assess whether patients hospitalized in beds physically adjacent to critically ill patients are at increased risk to acquire multidrug-resistant pathogens. DESIGN: Cohort study.Setting. Shaare Zedek Medical Center, a 550-bed medical referral center. PATIENTS: From April to September 2004, we enrolled consecutive newly admitted patients who were hospitalized in beds adjacent to either mechanically ventilated patients or patients designated as "do not resuscitate" (DNR). For each of these patients, we also enrolled a control patient who was not hospitalized in a bed adjacent to a critically ill patient. We collected specimens from the anterior nares, the oral cavity, and the perianal zone at the time of admission and subsequently at 3-day intervals until discharge or death. Specimens were cultured on selective media to detect growth of antibiotic-resistant pathogens, including Acinetobacter baumannii, methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum beta lactamase (ESBL)-producing Enterobacteriaceae, and vancomycin-resistant enterococci (VRE). RESULTS: We enrolled 46 neighbor-control pairs. Among neighbors and controls, respectively, the incidence rates for isolation of A. baumannii was 8.3 and 4 isolations per 100 patient-days (relative risk [RR], 2.1 [95% confidence interval {CI}, 0.8-5.2]; P=.12), the incidence rates for MRSA were 1.4 and 2.6 isolations per 100 patient-days (RR, 0.6 [95% CI, 0.1-2.3]; P=.45), the incidence rates for ESBL-producing Enterobacteriaceae were 10.5 and 9 isolations per 100 patient-days (RR, 1.2 [95% CI, 0.6-2.4]; P=.84), the incidence rates for VRE were 4.3 and 4.8 isolations per 100 patient-days (RR, 0.9 [95% CI, 0.3-2.4]; P=1), and the composite incidence rate was 21.7 and 16.2 isolations per 100 patient-days (RR, 1.3 [95% CI, 0.8-2.3]; P=0.3). CONCLUSIONS: In this pilot study, we did not detect an increased incidence rate of isolation of multidrug-resistant pathogens among patients hospitalized in beds adjacent to critically ill patients. Further studies with larger samples should be conducted in order to generate valid data and provide patients, physicians, and policy makers with a sufficient knowledge base from which decisions can be made.     

传染病患者多重耐药菌携带的风险因素筛查研究

目的 通过建立传染病危重患者院内多重耐药菌(multidrug-resistant organisms, MDROs)感染的风险模型,在获取病原学检测结果前预测患者院内MDROs感染的概率,及时开始经验性多耐药管理,降低院内传播风险。方法 对230例患者进行回顾性分析,应用单因素分析寻找影响MDROs的因素,并对这些因素采用logistic回归分析的方法构建风险模型,通过受试者工作特征(receiver operating characteristic, ROC)曲线比较不同指标的预测价值。结果 通过单因素分析显示,11个因素差异有统计学意义。采用logistic回归分析,最终得到一个包含留置动脉导管、血液净化、纤维支气管镜肺泡灌洗、培养出耐药菌前抗生素使用种类和重症监护室(intensive care unit,ICU)住院天数共5个变量的模型,模型的误判率为25.7%,说明模型的预判效果较为理想。留置动脉导管、血液净化、纤维支气管镜肺泡灌洗、培养出耐药菌前抗生素使用种类、ICU住院天数及联合因子对传染病危重患者携带MDROs预测的ROC曲线下面积分别为0.615、0.553、0.5...     

多重耐药铜绿假单胞菌耐药基因的检测与分析

目的:调查我院多重耐药铜绿假单胞菌β-内酰胺酶编码基因、外膜通道蛋白D2(OprD2)基因、氨基糖苷类修饰酶基因和耐消毒剂基因的存在状况。方法:采用K-B法测定临床分离的铜绿假单胞菌对17种抗菌药物的药物敏感性,筛选出100株多重耐药菌株,采用聚合酶链反应检测β-内酰胺酶编码基因、OprD2基因、氨基糖苷类修饰酶基因和耐消毒剂基因。结果:100株多重耐药铜绿假单胞菌中β-内酰胺酶编码基因CTX-M-1群、TEM、DHA的检出率分别为54.0%、30.0%、9.0%,未检出SHV、OXA-10群、PER、GES、VEB、CARB、IMP和VIM基因;OprD2基因的缺失率为61.0%;氨基糖苷类修饰酶基因aac(6′)-Ⅱ、ant(3″)-Ⅰ和ant(2″)-Ⅰ的阳性率分别为59.0%、33.0%、25.0%,未检出aac(6′)-Ⅰ;耐消毒剂基因qacE△1-sul1的检出率为15.0%。结论:我院多重耐药铜绿假单胞菌存在多种耐药基因,对β-内酰胺类抗生素的耐药主要与CTX-M-1群、TEM、DHA型耐药基因有关,对亚胺培南耐药主要与OprD2基因缺失有关,对氨基糖苷类抗生素的耐药主要与aac(6′)-Ⅱ、a...     

铜绿假单胞菌中氨基糖苷类基因的分布与耐药性研究

目的 了解医院临床分离的多药耐药铜绿假单胞菌(MDRPA)中氨基糖苷类修饰酶(AMEs)基因存在状况.方法 收集临床2010年9-11月分离的铜绿假单胞菌40株进行氨基糖苷类基因检测,采用PCR法检测;统计铜绿假单胞菌的药敏结果,并分析氨基糖苷类基因和耐药性之间的关系.结果 40株铜绿假单胞菌中36株检出耐药基因,检出率为90.0％,PCR扩增出8种氨基糖苷钝化酶基因,大部分菌株均产生氨基糖苷钝化酶,其次为乙酰转移酶(ACC)和核苷转移酶(ANT),acc3Ⅱ、ant6Ⅰ、acc3Ⅳ、acc3Ⅰ、ant(3")Ⅰ基因的阳性率分别为80.0％、55.0％、25.0％、15.0％及7.5％.结论 医院临床分离的多药耐药铜绿假单胞菌中AMEs基因携带率很高,至少存在5种AMEs基因,分别为aac(3)Ⅱ、ant(6)Ⅰ、acc(6′)Ⅰ、acc(3)Ⅰ和ant(3″)Ⅰ.     

多药耐药铜绿假单胞菌的菌株亲缘性分析

目的 分析20株多药耐药铜绿假单胞菌(MDRPA)的药敏率及菌株亲缘性关系,为医院感染实时监测提供参考依据.方法 收集柳州市三级医院2011年1-12月标本中分离的MDRPA共20株,采用聚合酶链反应(PCR)的方法分析33种β-内酰胺酶基因、15种氨基糖苷类修饰酶基因、6种16S rRNA甲基化酶基因、15种可移动遗传元件标记基因、oprD2膜孔蛋白基因,并对检测结果作样本聚类分析.结果 20株多药耐药铜绿假单胞菌对庆大霉素、妥布霉素、阿米卡星、环丙沙星、左氧氟沙星的耐药率均为60.00％,敏感率均为40.00％;样本聚类分析示存在7个克隆传播.结论 MDRPA携带获得性耐药基因可导致对相关抗菌药物耐药,且可移动遗传元件的水平转移,使细菌的耐药性在同种细菌之间甚至不同种细菌之间得以快速传播.     

多药耐药铜绿假单胞菌耐药基因的研究

目的 了解临床分离的多药耐药铜绿假单胞菌的耐药性及相关基因存在状况,为临床抗菌药物应用提供依据.方法 对分离的49株铜绿假单胞菌用Microscan公司肉汤稀释法药敏板测定15种抗菌药物的敏感性;用聚合酶链反应(PCR)法检测49种铜绿假单胞菌相关耐药基因及外膜通道蛋白oprD2基因,并作R型聚类分析.结果 多药耐药铜绿假单胞菌对氨基糖苷类的阿米卡星与喹诺酮类的左氧氟沙星耐药率耐药率相对较低,分别为24.5％、38.8％,对β-内酰胺酶类、头霉素类、碳青霉烯类、β-内酰胺酶与酶抑制剂复合物等抗菌药物的耐药率均＞60.0％,提示试验菌株包含不同种类的耐药基因;49株多药耐药铜绿假单胞菌存在13种不同类型的β-内酰胺酶基因,其中A类与D类β-内酰胺酶基因的检出率较高,C类与B类β-内酰胺酶基因较低;A类有PER、TEM、SHV、CTX-M-13型等基因,分别占28.6％、32.7％、46.9％、2.0％;D类有OXA-10、OXA-14、OXA-17、OXA-2、OXA-23、OXA-51等基因,分别占24.5％、8.2％、6.1％、2.0％、4.1％、6.1％;C类检出DHA和MOX基因,分别占14.3％和6.1％;B类检出VIM2基因,占6.1％;检出3种氨基糖苷类修饰酶基因:aac(3)-Ⅰ(4.1％),aac(3)-Ⅲ(8.2％),aac(6')-Ⅰb-Cr(2.0％),以aac(3)-Ⅲ最多;检出喹诺酮类耐药qnrB2与qnrB4基因,分别占6.1％和2.0％;检出oprD2基因高达85.7％;检出整合子遗传标志Int I1基因有5株,占10.2％;检出获得性抗菌制剂外排泵基因qacE 1-sull基因有2株,占4.1％.结论 49株多药耐药铜绿假单胞菌对头孢菌素耐药主要与A类与D类β-内酰胺酶基因有关;oprD2基因的存在是铜绿假单胞菌对亚胺培南耐药的主要原因.     

多重耐药铜绿假单胞菌氨基糖苷类修饰酶基因研究

目的:了解铜绿假单胞菌氨基糖苷类修饰酶基因存在情况,为耐药性监测提供依据。方法:采用VITEK-32配套GNS-448及K-B法测定铜绿假单胞菌对抗菌药物的敏感性,采用聚合酶链反应及序列分析的方法分析氨基糖苷类修饰酶基因类型。结果:20株多重耐药铜绿假单胞菌对亚胺培南、美洛培南全部耐药,哌拉西林/他唑巴坦、头孢吡肟及头孢他啶的耐药率分别为90.0%、100%和85%,氨基糖苷类抗生素的耐药率为阿米卡星85.0%、庆大霉素100%,对其他抗菌药物的耐药率均在85.0%以上。20株铜绿假单胞菌中检出5株aac(6)′-Ⅰb、1株aac(6)′-Ⅱ、15株ant(3)′-Ⅰ、8株ant(2)′-Ⅰ,阳性率分别为25%、5%、75.0%、40%。其他基因型阴性。结论:本院重症监护病房临床分离的铜绿假单胞菌多重耐药严重,氨基糖苷类修饰酶基因携带率较高。     

Risk factors for multidrug-resistant Pseudomonas aeruginosa nosocomial infection

A case-control study was conducted in a university hospital to determine the risk factors for nosocomial infection with multidrug-resistant Pseudomonas aeruginosa (MDR-PA) among all hospitalized patients and among those with a nosocomial infection due to P. aeruginosa. Eighty patients infected with MDR-PA, 75 infected with a non-MDR phenotype and 240 random controls were included in the 12-month study. Among all hospitalized patients, age, severity index, having a bedridden condition, transfer from other units, nasogastric feeding, urinary catheterization and exposure to beta-lactams (OR=2.5) or fluoroquinolones (OR=4.1) in the seven days before infection were linked to nosocomial infection due to MDR-PA. Among patients infected by P. aeruginosa, exposure to fluoroquinolones (OR=4.7) or surgery (OR=0.5) were linked to the isolation of MDR-PA. This study showed that, in addition to urinary catheterization, nasogastric feeding is an important risk factor in MDR-PA infection. Indeed, an imbalance in gut flora, modifications to the mucous membranes due to the use of nasogastric feeding and the selection pressures exerted by antibiotics were implicated in the occurrence of this infection.     

多药耐药铜绿假单胞菌的耐药现状

目的 探讨医院多药耐药铜绿假单胞菌( MDRPA)的耐药特性,为临床医师合理使用抗菌药物提供实验室参考依据.方法 细菌培养严格按照《全国临床检验操作规程》进行;细菌鉴定采用法国生物梅里埃公司提供的API板条和软件系统;采用K-B法进行药敏试验,结果评价依据CLSI最新版本.结果 205株MDRPA中泛耐药株检出率为12.7％; MDRPA对亚胺培南、美罗培南、哌啦西林/他唑巴坦、头孢哌酮/舒巴坦已产生了12.7％,～15.1％的耐药率,对其他常用抗菌药物的耐药率为30.0％～71.0％,且耐药率呈上升趋势.结论 医院务必加强抗菌药物使用管理,坚持进行细菌耐药性监测,遏制细菌耐药性快速增长的不良趋势.     

Monitoring therapeutic interventions in critically ill septic patients.

Sepsis is the leading cause of admission to intensive care units in the United States. Although the treatment of sepsis is complex and multimodal, nutrition support plays an important role in the management of these patients. The diagnosis of sepsis, disease category, and severity of illness and the change in sepsis severity and organ function over time affect the delivery of nutrition support. This paper reviews the diagnostic criteria of sepsis, the use of "sepsis biomarkers," and regional and global markers of organ function in sepsis and quantitative measures of illness severity and organ dysfunction.     

Insulin therapy in critically ill patients

PURPOSE OF REVIEW: The recent publication of the results of an aggressive approach to the treatment of hyperglycaemia in critically ill patients, and a rekindling of interest in the use of an infusion of glucose insulin and potassium as adjunctive therapy in a diverse group of patients with cardiovascular disease, warrants a review of the multiple effects of insulin and a review of laboratory and clinical studies. RECENT FINDINGS: The use of an aggressive protocol to maintain normoglycaemia in critically ill patients has been demonstrated to be a beneficial technique in the critical care setting. Implementation of the protocol outside of a research setting appears to be feasible. Recent studies on the use of insulin in addition to glucose and potassium in patients with diverse cardiovascular diseases have also demonstrated positive results. SUMMARY: This review will summarize some of the putative beneficial effects of insulin as a pharmacological agent, and review recent clinical data. Although the relative benefits of normoglycaemia in the critical care setting and the beneficial effects of insulin are difficult to differentiate, a substantial overlap exists. The extent to which these converging therapies (aggressive normoglycaemia and insulin pharmacotherapy) will be applicable to diverse clinical settings has yet to be determined.     

Muscle function in critically ill patients

Endotoxemia and inflammation (cytokines) lead to an acute decrease of the muscle resting membrane potential, loss of the sodium-potassium gradient and to an increase in cytosolic Ca(2+) in critically ill intensive care unit patients. As a consequence, muscle (and nerve) contractility is reduced. As a consequence also, amino acid gradients are reduced, proteolysis is increased, the mitochondrial density is reduced to levels as low as 10% of normal within 2-3 days and cellular substrate metabolism is impaired. The author of this paper proposes that treatment modalities in clinical nutrition should primarily aim at improving muscle function and restoring muscle membrane potential and that these variables should be used as the primary outcome variables of clinical trials. Attempts to modify these measurements such that they can be used routinely in the ICU setting are ongoing in our group. Muscle protein and substrate metabolism can only be normalized when these primary variables have successfully been restored. The use of muscle relaxants may lead to a functional denervation of the muscle, to changes in the molecular structure of the myofibrils and may postpone a successfull recovery. Learning objectives: Causes of muscle weakness and loss of contractility in ICU patients; Relation between loss of contractility and impairments in muscle metabolism; Muscle function as an endpoint variable for clinical nutrition interventions.     

Endemic carbapenem-resistant Pseudomonas aeruginosa with acquired metallo-beta-lactamase determinants in European hospital

Acquired metallo-beta-lactamases (MBLs) can confer broad-spectrum beta-lactam resistance (including carbapenems) not reversible by conventional beta-lactamase inhibitors and are emerging resistance determinants of remarkable clinical importance. In 2001, multidrug-resistant Pseudomonas aeruginosa carrying bla(VIM) MBL genes were found to be widespread (approximately 20% of all P. aeruginosa isolates and 70% of the carbapenem-resistant isolates) at Trieste University Hospital. Clonal diversity and heterogeneity of resistance determinants (either bla(VIM-1)-like or bla(VIM-2)-like) were detected among MBL producers. This evidence is the first that acquired MBLs can rapidly emerge and establish a condition of endemicity in certain epidemiologic settings.     

Acquisition of multidrug-resistant Serratia marcescens by critically ill patients who consumed tap water during receipt of oral medication.

We describe an outbreak of multidrug-resistant Serratia marcescens infection and colonization involving adults admitted to a surgical intensive care unit. Examination of the outbreak revealed epidemiological evidence that consumption of tap water from a contaminated faucet during receipt of oral medication was the mechanism of S. marcescens acquisition.     

Genotypes and infection sites in an outbreak of multidrug-resistant Pseudomonas aeruginosa

There is little published evidence regarding whether heparin lock solutions containing preservatives prevent catheter-related infections. However, adverse effects from preservative-containing flushes have been documented in neonates, leading many hospitals to avoid their use altogether. Infection control records from 1982 to 2008 at St. Jude Children's Research Hospital (SJCRH) were reviewed regarding the incidence of catheter-related infections and the use of preservative-containing intravenous locks. In addition, the antimicrobial activities of heparin lock solution containing the preservatives parabens (0.165%) or benzyl alcohol (0.9%), and 70% ethanol were examined against Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Bacillus cereus, Pseudomonas aeruginosa and Candida albicans, and compared with preservative-free saline with and without heparin. Growth was assessed after exposure to test solutions for 0, 2, 4 and 24h at 35 °C. The activities of preservatives were assessed against both planktonic (free-floating) and sessile (biofilm-embedded) micro-organisms using the MBEC Assay. Infection control records revealed two periods of increased catheter-related infections, corresponding with two intervals when preservative-free heparin was used at SJCRH. Heparin solution containing preservatives demonstrated significant antimicrobial activity against both planktonic and sessile forms of all six microbial species. Ethanol demonstrated the greatest antimicrobial activity, especially following short incubation periods. Heparin lock solutions containing the preservatives parabens or benzyl alcohol, and 70% ethanol demonstrated significant antimicrobial activity against both planktonic and sessile micro-organisms commonly responsible for catheter-related infections. These findings, together with the authors' historical infection control experience, support the use of preservatives in intravenous lock solutions to reduce catheter related infections in patients beyond the neonatal period.     

多药耐药铜绿假单胞菌在神经外科暴发的调查

目的 回顾性分析神经外科铜绿假单胞菌(PAE)下呼吸道感染医院暴发原因及控制措施,探求引起多药耐药PAE感染可能存在的危险因素.方法 对PAE感染患者以流行病学方法进行调查、分析,辅以环境监测及细菌鉴定.结果 该次PAE医院感染暴发主要以消毒不严格的螺纹管及雾化管道所致,呼吸机螺纹管及雾化管道PAE检出率为100.0％,患者家属的手PAE检出率为80.0％;由于环境中PAE感染源的持续存在以及抗菌药物长时间、联合应用促进了多药耐药PAE的感染.结论 将PAE感染患者统一隔离,并采取严格的消毒措施、加强护理,严格抗菌药物的使用等,有效控制PAE医院感染的再扩大.